Use Element& instead of Element* as a parameter of HasEquivalentAttributes

When HasEquivalentAttributes is called, Element object was passed as
a parameter.
and it is never nullptr. so it can be changed to reference instead of pointer.

Bug: 874385
Cq-Include-Trybots: luci.chromium.try:linux_layout_tests_layout_ng
Change-Id: I237a11e88236ef195ade12ee26b0722786f17e29
Reviewed-on: https://chromium-review.googlesource.com/1232810Reviewed-by: Hayato Ito <hayato@chromium.org>
Commit-Queue: Hwanseung Lee <hs1217.lee@samsung.com>
Cr-Commit-Position: refs/heads/master@{#592681}

third_party/blink/renderer/core/dom/element.cc

@@ -1981,15 +1981,15 @@ void Element::ParserSetAttributes(const Vector<Attribute>& attribute_vector) {
   }
 }
 
-bool Element::HasEquivalentAttributes(const Element* other) const {
+bool Element::HasEquivalentAttributes(const Element& other) const {
   SynchronizeAllAttributes();
-  other->SynchronizeAllAttributes();
-  if (GetElementData() == other->GetElementData())
+  other.SynchronizeAllAttributes();
+  if (GetElementData() == other.GetElementData())
     return true;
   if (GetElementData())
-    return GetElementData()->IsEquivalent(other->GetElementData());
-  if (other->GetElementData())
-    return other->GetElementData()->IsEquivalent(GetElementData());
+    return GetElementData()->IsEquivalent(other.GetElementData());
+  if (other.GetElementData())
+    return other.GetElementData()->IsEquivalent(GetElementData());
   return true;
 }
 

third_party/blink/renderer/core/dom/element.h

@@ -502,7 +502,7 @@ class CORE_EXPORT Element : public ContainerNode {
   // Clones attributes only.
   void CloneAttributesFrom(const Element&);
 
-  bool HasEquivalentAttributes(const Element* other) const;
+  bool HasEquivalentAttributes(const Element& other) const;
 
   // Step 5 of https://dom.spec.whatwg.org/#concept-node-clone
   virtual void CloneNonAttributePropertiesFrom(const Element&,

third_party/blink/renderer/core/dom/node.cc

@@ -1343,7 +1343,7 @@ bool Node::isEqualNode(Node* other) const {
     if (ToElement(this)->TagQName() != ToElement(other)->TagQName())
       return false;
 
-    if (!ToElement(this)->HasEquivalentAttributes(ToElement(other)))
+    if (!ToElement(this)->HasEquivalentAttributes(ToElement(*other)))
       return false;
   } else if (nodeName() != other->nodeName()) {
     return false;

third_party/blink/renderer/core/editing/commands/editing_commands_utilities.cc

@@ -138,7 +138,7 @@ bool AreIdenticalElements(const Node& first, const Node& second) {
   if (!first_element.HasTagName(second_element.TagQName()))
     return false;
 
-  if (!first_element.HasEquivalentAttributes(&second_element))
+  if (!first_element.HasEquivalentAttributes(second_element))
     return false;
 
   return HasEditableStyle(first_element) && HasEditableStyle(second_element);